#define _CRT_SECURE_NO_WARNINGS
#include <stdio.h>

int main()
{again:
	int empty = 0;
	int total = 0;
	int money = 0;
	scanf("%d", &money);
	total = money;
	empty = total;
	while (empty >= 2)
	{
		total += empty / 2;
		empty = empty % 2 + empty / 2;
	}
	printf("%d\n", total);
	goto again;
	return 0;
}